FIX: fix module install - manages_content field

app/Models/Module.php

@@ -5,6 +5,7 @@ namespace App\Models;
 use App\Handlers\Contracts\AppHandler;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Support\Facades\App;
+use Modules\Blog\Article\Handlers\Article;
 
 /**
  * Class Module
@@ -43,7 +44,7 @@ class Module extends Model
             throw new \ErrorException('Modules can be installed only via Artisan!');
         }
 
-        $managesContent = $handler instanceof AppHandler;
+        $managesContent = in_array('App\Handlers\Contracts\AppHandler', class_implements($handler));
         $supportCategories = $managesContent ? call_user_func([$handler, 'supportCategories']) : false;
 
         // insert module into database